Aberdeen's own mother-daughter singing sensation are through to the semi-finals of TV smash-hit Britain's Next Big Star. They're in all the gossip magazines, they've got millions of YouTube hits, everyone loves them. But their reality-TV dream has turned into a real-life nightmare. The ransom demand appears in all the papers, on the TV, and the internet, telling the nation to dig deep if they want to keep Alison and Jenny alive. The media want action; the public displays of grief and anger are reaching fever-pitch. Time is running out, but DS Logan McRae and his colleagues have nothing to go on: the kidnappers haven't left a single piece of forensic evidence.